I've recently built the newer S3tlm's with the Magnesium driver and newer ribbons, I used to have the same S3tlm's as you guys but one got damaged so decided to go for the newest ones for a change.

The cabs are the same, the only difference is the cut out hole for the new ribbon.
The crossovers are also different, theres a 10uf Alcap in the Magnesium part of the filter, I wanted to change this to polypropylene but Ivan advised me not to he knows more about these speakers than me so I'll leave them in for now.
Theres the 5uf cap in the ribbon part which is the same red cased polypropylene as the older ones, the resistors etc are different values.

Mine still need veneering so I'll post some pictures when they are finished.

The sound so far is very good, adjusting the amount of wool behind the magnesium driver and teasing it out makes quite a big difference, to start with I had far too much bass but after some tweaking about the sound is much better

I used 10R caddock resistors in my other IPL's which sounded better than those white sand filled ones to my ears, I also tried the MOX10 from Audiocom but preferred the Caddocks.
Jon, the Caddocks are no longer needed because the values in these new crossovers are different so I'll send them you

In summary, these TL speakers were absolutely superb and were not in any way inappropriate for or outclassed by the Krell. I always suspected they had more headroom to deal with more amplification than I was feeding them, and I was right!